Reg #2.
No, originally Chrome sent 'Cache-Control: max-age=0' for all resources in reloads. This was too aggressive today because now developers have the Inspector as a right tool to debug the web.
After the modification, Chrome sends it only for the main resource, but just follows the protocol for sub-resources. That means Chrome will uses cached contents only when the cached contents are allowed to be reused, e.g. not expired.